"key algorithm" in GnuPG's signature verification output

[MFPA]

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Hash: SHA512



When verifying a signature using GnuPG, it seems the line (eg):-

textmode signature, digest algorithm SHA512


has become:-

textmode signature, digest algorithm SHA512, key algorithm rsa2048


Unless I am mistaken, the key algorithm given is that of the primary
key. I just wondered why not the subkey algorithm, where the signature
was made using a signing subkey?


I was slightly confused to read:-

gpg: Signature made 06/12/2014 13:13:11 GMT Standard Time
gpg:                using EDDSA key 0x1712BC461AF778E4
gpg: using subkey 0x1712BC461AF778E4 instead of primary key
     0x251BCCEB547B7194
gpg: Good signature from "MFPA" [ultimate]
     Primary key fingerprint: 1755 EFD8 AEDE E4AD 9198  90C5 251B CCEB
     547B 7194
     Subkey fingerprint: 33AC ED4E E913 4EEB DE6A  8506 1712 BC46 1AF7
     78E4
gpg: binary signature, digest algorithm SHA512, key algorithm rsa2048

(My confusion was the second line saying "using EDDSA key" but the
last line saying "key algorithm rsa2048".)

- --
Best regards

MFPA                    mailto:2014-667rhzu3dc-lists-groups at riseup.net

The cure for anything is salt water - sweat, tears, or the sea.
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